Increasing stability and productivity of lipase-enzyme by encapsulation in a porous organic-inorganic system

In this work we report the encapsulation of lipase enzyme in highly ordered mesoporous matrix, by a sol-gel method that involves the hydrolysis/polycondensation of a silica precursor at neutral pH and room temperature. The enzyme is encapsulated within the micellar phase of the surfactant that is self-assembled with silica. The encapsulated biocatalyst has been used for the transesterification reaction of triolein with methanol under solvent free conditions. The highest fatty acid methyl esters yield (77%) was obtained after 96 hours at 40°C, with triolein:methanol molar ratio equal to 1:3 and with a very low amount of enzyme. Total productivity of the immobilized enzyme is almost 6 times higher than the one obtained using free lipase. The results clearly indicate that the immobilization procedure of lipase preserves the mobility of the enzyme and allows to increase its stability.